CVE-2026-5269

Critical

Description

In Ciena's Navigator Network Control Suite (NCS) and Manage Control Plan (MCP), there are hidden system accounts used for internal software operations. Some of these accounts have default passwords that may be predictable. While these accounts have very limited permissions on their own, an attacker could combine an attack using one of these accounts with other potential weaknesses to launch a more significant attack, possibly leading to escalation of privilege on the system.

SeverityCritical
CVSS9.8
Exploit probability—
ProductNavigator NCS
PublishedJul 14, 2026
First seenJul 14, 2026
Weakness typeCWE-1393CWE-1393

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
CIENA Navigator NCS8.1—
CIENA MCP<= 8.0—
CIENA Planner Plus OnPrem<= 4.1—

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